I have a self-built system for pretty-much this built around a Supermicro board X11SCH-LN4F with Xeon E-2146G. I have 8 drives (not hot-swap) in a ZFS array, plus nvme for the OS, and I use Noctuas all round. Not silent but quiet enough. Idles around 80w and I run a number of containers/VMs on it as well as storage. I went with a low end 4U case with shallow 45cm depth.

The motherboard takes up to 128GB ECC UDIMMS and has 4 ethernet ports (plus a 5th for IPMI) and a good number of SATA ports (I am running 8 drives without additional cards).

I have enterprise rackmount gear as well and my DIY box is in a different league silence-wise (and efficient low-idle CPU wise as well).

If building today, the equivalent current CPU is, I think, E-2246G.

What power strip? Kenable sell individually switched ones for around £35, pulse is the brand. I just bought 3 of them.

Not in a position to try this right now, but if your server is a Dell and you have the (enterprise, possibly) iDRAC, I think you can make a light on the drive caddy blink so you can identify it.

The important digit is the middle one which is the generation and x10 is oldest. Current gen is x60. The x is type with 1 being mist basic 1 CPU box and it goes up from there. Odd numbers tend to be 2u and even 1u but there are exceptions to that. The 0 on the end means Intel, a 5 would be amd.

Just wanted to add that I got a T400 and it fits lovely in my R640 low-profile slot and no complaints. Works great, passed through to VM.

I asked a similar thing the other day but about a 640. The problem I have is a power error during boot that requires F1 to continue but otherwise works fine. The docs mention supporting up to 3 nvidia T4 series cards. Is that Tesla and would that include T400 which looks like it would fit. I just want to avoid the boot error if I can.